Lubricating oils



April 17, 1 934: F. w. SULLIVAN, JR., r AIL 1, 5,

- LUBRICATING OILS Filed Marh 15, 1929 2 Sheets-Sheet 1 P 1934- F, w. SULLIVAN, JR, ET'AL 1,955,260

' LUBRICATING OILS I Filed March 15, 1929 2 Sheets-Sheet 2 2 a Fnden'af rmwlm, Jz,

' particularly to lubricating oils resulting from the- Patented Apr. 17, 1934 UNITED STATES maximum oms Frederick W. Sullivan, Jr., and Vanderveer -Voorhees, Whiting, 1nd,, assignors to Standard Oil filmy, Whiting, Ind, a 1 corporation of Application March 15, 1929, Serial No. 347,446

16 Claim.

This invention relates to lubricating oils, and

action or aluminum chloride or other equivalent polymerizing agent. upon suitable hydrocarbon material, as hereinafter set forth.

The invention is illustrated by the accompanying .drawings, in which- 4 v Fig. l. is a graph of the equation hereinafter set forth, defining the limiting relationship of cold test to viscosity of oils prepared in accordance with the present invention.

Fig. 2 shows by graphs the comparative viscosity-temperature curves of typical'natural lubricant oils and oils prepared in accordance F with the present invention.

In accordance with this invention, we employ as the source of unsaturated hydrocarbon material what may be termed a high boiling product consisting largely or entirely of normal parafiin hydrocarbons. Forexample, we may use hydrocarbon waxes, which are now well understood to consist substantially of straight-chain parafiin hydrocarbons. This wax may'suitably be paraflin wax which occurs in Pennsylvania and Mid-Continent crude petroleum or other waxy material, such as petrolatum, slop-wax, ozokerite wax or other hydrocarbon waxes. It must be understood, however, that the term "straightchain hydrocarbon material is not limited to waxes, since it is obvious that-in oils containing wax, there is undoubtedly present straight-chain material of similar character, but of smaller molecular weight so that they do not solidify as y readily as the ordinary waxes.

Thus, it is well recognized that Pennsylvania oil, for example, gas, oil, contains more normal paraflin hydrocarbon material than does a similar distillate derived from Mid-Continent crude petroleum, while the latter likewise contains more straight-chain material than do similar oils derived-from Coastal crudes. We may define our high boiling normal paraflin hydrocarbon material as one containing a larger amount or percentage of normal paraflin hydrocarbons than does a similar representative Pennsylvania distillate oil, and containing substantial proportions of constituents having a" boiling point under atthe normal hydrocarbons to pyrolysis, as will be.

hereinafter described.

In producing improved lubricating oils according to this invention, wefirst'crack the highboiling normal paraffin hydrocarbon material to temperature and pressure may materially affect the ultimate yield.

The distillate from such a cracking process may be redistilled to give a fraction substantially free of waxy material. Thus, we find ,ordinarily that if the end-point of such fraction is carried much above 500 F. the lubricating oils produced =therefrom have an undesirably high cold test. When a distillate of about 500 F. end-point is .polymerizedto a lubricating oil, this oil will contain no apparent wax. On reduction of the polymerized oil, both the light overhead and the high viscosity bottom will have a low cold test. If desired, the distillate from the cracking operation may be fractionated into several'portions which may be separately polymerized to products containing higher proportions of lighter or heavier lubricant products according to the nature of the cracked fraction employed.

In polymerizing the cracked fraction we may suitablyemploy from 0.5 to 4% of anhydrous alumifiumihloride, but excellent results may be secured with larger and occasionally with smaller proportions. We also prefer to conduct the polymerization at a temperature between and 250 F. a longer period of time being required at lower temperatures and a higher yield of more vis ous products ,being produced. Dur-' I ing the polymerization the mixture is thoroughtain the maximum yield of lubricating'oil.

Aftenpolymerization, it is necessary to separate tar or aluminum chloride sludge from the oil. Most of the tar settles on standing and can .be drawn off, leaving a brownoil containing particles of suspended tar. order to obtain oils of the best color and lowest Conradson carbon, it is desirable to remove the remaining suspended tar. This may suitably be done by filtering with a small quantity of adsorbent earth, such as clay lines, or by prolonged settling, for example, 48 hours at 100-150 F. The oil may then be washed with an alkaline solution, as a 5 to 10% solution of caustic soda, ifneutralization is required. The oil is then reduced by steam and fire or vacuum distillation to remove light oils andnaphtha leaving a lubricating residue which may be separated by distillation to yield lubricating oils of desired viscosity.

The invention will more readily be understood from the following detailed. description of a. specific example:

A wax product derived, such as slack wax or a sweat oil (for example, 110-120 melt) from Mid-Continent oil, containing 85% of mineral wax, the remainder being oil, is vaporized and the vapors heated at atmospheric pressure to a temperature between 900 and 980 F. to bring about cracking. After cracking, the vapors are separated from tar and are fractionated and condensed to yield a distillate having an end-point of about 500 F. The tar is eliminated and the intermediate condensate is recycled and cracked with the feed. It is preferred to operate to produce between 10 and 25% of distillate per pass. During this cracking operation, 28% of gas, 5% of tar and 67% of distillate by weight are produced.

To such distillate about 1 to 3% of anhydrous aluminum chloride is added and the charge is maintained at about 210 F. for about 18 hours with thorough stirring. At the end of this period, the stirring is stopped and the tar, which amounts to about '7 to 10% of the initial charging stock is allowed to settle and is removed.

The remaining oil is reduced with steam; about 10% of light distillate, of oil of 90 viscosity (210 F.), and about 10% of tar are produced. The heavy oil has the following inspection, after filtering through a small quantity of clay to secure the desired color:

Gravity, 32.5 A. P. 1.;fiash, 500 EH; pour, -25 F.; viscosity at 210 F., 90 sec. Saybolt; viscosity at 100 F. 850 to 900 sec. Salbolt; Conradson carbon 0.13%; color 2 N. P. A.

Of course, it must be understood that other lubricating oils may be produced by a suitable control of the distillation. Thus, we may take off 10% of light distillate; 27.6% of oil of viscosity between 95 and 105 sec. Saybolt at 100 F.; 3.3% of oil of viscosity between 250 and 275 sec. Saybolt at 100 F.; and leave a bottom consisting of 49% of oil of viscosity of 190 sec. Saybolt at 210 F. The inspection of this bottom after claying is as follows:

Gravity, 31 A. P. 1.; flash, 620 F.; pour -5 R; viscosity at 210 F. 190 sec. Saybolt; viscosity at 100 F., 3000 sec. Saybolt; Conradson carbon 0.33%; color, 4 N. P. A. The yields of the lubricating oils thus obtained, based on the wax charging stock, are 48.6% of 90 viscosity oil and 28% of 190 viscosity oil (viscosities at 210 F.)

The aluminum chloride sludge may be reused on fresh oil to be polymerized to efiect the desired change in whole or in part. Thus the cracked distillate treated may first be subjected to the action of sludge from previous treatment, and subsequently to' the action of fresh anhydrous aluminum chloride. The sludge resulting from the latter step may then be used in treating fresh distillate.

The oils produced according to the present intin uish them from all lubricating oils known to applicants. Thus, We can produce oils which have a substantially better viscosity-temperature gradient than Pennsylvania lubricating oils, which possess very remarkable cold test properties and show a low- Conradson carbon test.

As indicated above many of the new oils produced according to our invention possess a lower temperature coefficient of viscosity than Pennsylvania lubricating oils. It will be understood that oils of various degrees of viscosity can be produced which will have a viscosity-temperature gradient less than that of a Pennsylvania oil of similar viscosity. For convenience, we will give the Saybolt viscosity of various oils at two arbitrary temperatures, viz. 100 F. and 210 F.

and will compare the viscosity change with a standard Pennsylvania lubricating oil of the same viscosity at the lower temperature. Thus, with wax derived from Mid-Continent crude petroleum containing about 15 or 25% of oil as starting material, the finished lubricating oil has a viscosity-temperature gradient substantially the same as that of Pennsylvania lubricating oil. With higher percentages of wax the lubricating oil has a lower temperature co-efficient of viscosity than Pennsylvania as indicated by the specific example given above, while an even better gradient is obtained with more purifled wax with a parafiin base oil which is richer in straight line hydrocarbon material than is Mid-Continent oil, the effect of oil content of the wax is not so marked.

It must be understood that our invention is not limited to oils having a viscosity-temperature gradient better than Pennsylvania oils, since it comprises many oils which have outstanding valuable properties, but which, nevertheless, may have a temperature co-efficient of viscosity equal to or not quite so good as Pennsylvania oil; an oil may be made having a lower temperature-viscosity co-eficient than for example, a Mid-Continent lubricating oil and at the same time a cold test lower than a coastal lubricating oil of the same viscosity at 100 F. with its normal wax content.

An important characteristic of our oils, both those superior to and somewhat inferior to Pennsylvania with respect to viscosity change with temperature is their low pour or solid points. This characteristic of our oils may suitably be expressed as follows:

log 11190 3:312 m wvm-lsc is plotted on semi-log coordinates, the abscissa representing the solid point in degrees Fahrenheit and the ordinates the logarithms of the viscosityin seconds Saybolt at 100 F. The points S1, S2, S3 and S4 indicate the positions on the graph of the correspondingly designated oils of the present invention in the table hereinafter set forth.

In addition to these characteristics, our lubrieating oils possessvery low Conradson carbon tests, very good color and very high flash points.

Thus, oils produced from material containing ventlon possess remarkable properties which diswax and upward as starting material have substantially higher flash points than Pennsylvania lubricating oils of similar viscosity at a standard temperature.

In order to ascertain more definitely the nature of our products, we give the following examples of oils of the first class, that is lubricating oils produced by the present process havingviscosity temperature gradients better than standard Pennsylvania or naraflln base lubricating oil of similar viscosity. These lubricating oils were produced substantially as described above, from the starting material indicated.

. y l Standard Penn- Lubncatmg oil of present in- S ylvama lubr1- vention eating on Initial stock Viscositysees. Viscosit insec.

Saybolt Say it G Cold A121. 0 w r" 85 a wax from 90 850-900 -30(S3) 32.5 90 950 .G.crude- 190 2800 l0(S4) 31 190 3000(12) o I 95% wax lrom 86' 675 -35(Sl) 34 86 860(P1) M. O. crudev Reflnedpetro- 87 735 36(S2) 34 87 900 In Fig. 2 of the drawings, curves of the temperature-viscosity relationships of typical natural oils are shown, the abscissa representing viscosities in seconds Saybolt at 210 F. and the ordinates representing viscosities in seconds Saybolt at 100 F. on a logarithmic scale. The curve designated C is typical of Coastal oils; that designated'MC, of Mid-Continent oils; that designated P of Pennsylvania oils, and that designated S of oils of the present invention. The points P1 and P2 desig hate the positions on the graph of they correspondingly marked Pennsylvania oils in the table above, and those marked S1, S2, and S4 of the correspondingly marked synthetic oils of the present invention in'the table above.

It may be noted that not only do these products show better temperature-viscosity characteristics than Pennsylvania lubricating oils, but they show high A. P. I. gravity and low cold test characteristics within'the definitions set forth above.

. As examples of lubricating oils which are not superior to Pennsylvania oils with respect to tem-' ,perature-viscosity gradient, but which are supe-Q rior to Mid-Continent or mixed base lubricating oils in that respect and which pos'sess remarkable 5 cold test properties within the aforesaid definitions, we give the following:

Standard Mid- Lubrlcatlng oil of our 0 ontinent, lubripmoess cating oil Initial stock Viscosity, Viscosity, sec.

secs. Saybolt Saybolt Cold F test ity 210 1 100! M V 210 F. 100 F.

' l F. wax from M.O.

crude oil 77 804 20 29.4 77 930(M1) wax from M.C.

crude oil 8d 835' -36 30.8 84 1120(M2) wax from M.C.

crude oil 83 840 20 30.0 83- 1100 Paraffin (va r) cracked; dlst ate I oi 200 F. endpoint '88 1083 -25 31.5 88' 1220 Paraflln (va r cracked; dist ate boiling between 200 and 310 F. 85 926 25 31. 3 85 1150 gravity which by Gruse, Petroleum and its tial quantities of olefines and derived by vapor rived from petroleum and consisting'predomiin the above table having the corresponding markings and the point M3 designates a typical Mid- Continent oil of a viscosity of 152 sec. Saybolt at 210 F. and 3200 see. Saybolt at 100 F. described Products, published 1928, on page 267. a

Although the present invention has been described in connection with the details of specific examples thereof, it must be understood that such details are not intended to be limitative of the invention, except in so far as set forth in the accompanying claims.

We claim:

'1. The method of producing lubricant oils which consists in polymerizing in the presence of a metallic halide catalyst the unsaturated hydrocarbon distillate products of cracking of hydrocarbon material containing a larger percentage of paraflin wax hydrocarbons than does distillate products of cracking of material containing substantial quantities of wax, and separating lubricating fractions therefrom.

3. The method of producing lubricating oils which consists in polymerizing with aluminum chloride, hydrocarbon distillate ,material containing substantial quantities of olefines and derived by vapor phase cracking from hydrocarbon material containing a. larger percentage of wax hydrocarbons than a Pennsylvania distillate oil.

4. The method of producing lubricating oils which consists in polymerizing with aluminum chloride, hydrocarbon distillate material containing substantial quantities of olefines and derived by vaporphase cracking from hydrocarbon material containing a substantial amount of wax.

5. The method of producing lubricating oils which consists in polymerizing with aluminum chloride, hydrocarbon material containing substantial quantities of olefines and .derived by vapor phase crackingfrom hydrocarbon material containing at least 65% of wax.

6. The method of producing lubricating oils which .consists in polymerizing with metallic halide, hydrocarbon material containingsubstanphase cracking from hydrocarbon material containing at least 75% of wax.

'7. The method of producing lubricating oils which consists in polymerizing with aluminum chloride hydrocarbon material containing a sub- 'of unsaturated hydrocarbons, subjecting such cracked material to polymerization with aluminum chloride, and separating lubricating oils therefrom.

9. The method of making lubricant oils which consists in subjecting hydrocarbon material. de'

nantly of wax to vapor phase cracking, polymerizing the cracked distillate product therefrom with aluminum chloride and separating lubricating oil therefrom.

stantial quantity of olefines and derived by Vapor 10. The method of producing lubricating oils which consists in subjecting petroleum wax to vapor phase cracking, fractionating the product thereof to obtain a distillate which is substane tially wax-free, polymerizing said distillate with aluminum chloride, and separating lubricating oil fractions from the polymerized material.

11. The method of producing lubricating oils which consists in cracking crude wax containing in excess of 80% of mineral wax at atmospheric pressure and a temperature between 900 and 1000 F., separating from the cracked products a distillate having an end-point around 500 F.,

polymerizing said distillate with about grams of anhydrous aluminum chloride per gallon of distillate at about 210 F. for about 18 hours,

separating sludge therefrom, removing light dis-- tillate and distilling to produce lubricating oil of desired properties.

12. The process of producing synthetic hydrocarbon lubricating oils characterized by abnormally low viscosity-temperature coefiicients; low specific gravity and low carbon forming tendency, which comprises treating paraflin wax to convert it into compounds of the type obtainable by pyrolytic cracking and comprising compounds having a straight chain carbon structure which are polymerizable with catalysts to give viscous hydrocarbon oils, subjecting said converted wax to the action of a metal halide catalyst whereby there is produced a viscous hydrocarbon oil and a metal halide sludge, separating said sludge and recovering and finishing the viscous oil.

13. The process of producing synthetic hydrocarbon lubricating oils characterized by abnor mally low viscosity-temperature coeflicients, low Specific gravity and low carbon forming tendency, comprising treating a hydrocarbon wax to produce straight chain unsaturated'hydrocarbons of a type similar to that obtainable by cracking. paraflinwax, and polymerizable with catalysts to give viscous hydrocarbon oils, subjecting said converted wax to the action of a metal halide catalyst whereby there is produced a viscous hydrocarbon oil and a metal halide sludge, separating said sludge and recovering and finishing the viscous oil.

Patent No. l, 955, 260.

viscous hydrocarbon oils, treating said material in a small amount of aluminum chloride at an I elevated temperature, thereby converting it into a viscous hydrocarbon oil and a sludge, and recovering the, viscous oil from said sludge.

15. The process of producing synthetic hydrocarbon lubricating oils characterized by abnor mally low viscosity-temperature coefficients, low specific gravity and low carbon forming tendency, comprising treating parafiin wax to convert it into compounds having a straight chain carbon structure which are polymerizable with catalysts to give viscous hydrocarbon oils, subjecting said converted wax to the action of a metal halide catalyst whereby there is produced a viscous hydrocarbon oil and a metal halide sludge, separating said sludge from the oil and recovering and finishing the viscous oil.

16. The process of producing synthetic hydrocarbon lubricating oils characterized by abnormally low viscosity-temperature coeflicients, low specific gravity and low carbon forming tendency, comprising converting hydrocarbon wax into straight chain hydrocarbon material of lower hydrogen content polymerizable by metal halide catalysts to give viscous hydrocarbon oils, treating said material with a small amount of aluminum chloride at an elevated temperature there- 'by converting it into a viscous hydrocarbon oil and a sludge, separating said sludge from said polymerized material and recovering and finishing the viscous oil.

'FREDERICK W. SULLIVAN, JR.

VANDERVEER VOORHEES.-

CERTIFICATE or connection.

April 17, 1934.

FREDERICK W. SULLIVAN, JR., ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Page 1, line 51, for

"mo'lecues" read molecules; page; 3, line 21, first column of the boxed table for "Refined petro-" read Refined petrolatum wax; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case'iu the Patent Office.

Signed andsealed this 15th day of May, A. D. 1934. I

(Seal) Bryan M. Battey Acting Conmissioner of Patents. 

